958 MOSQUITOES OF NORTH AMERICA 



with brilliant dark blue scales. Abdomen elongate ; dorsal vestiture deep blue, 

 at base with a greenish tinge, at apex shading into violet; lateral margins of 

 seoTnents silver marked with a yellowish tinge, expanded at apical angles of 

 sixth and seventh segments, which are also finely margined behind with silver; 

 vestiture of eighth segment almost black and with apical spots of yellowish 

 silvery scales ; claspers purple scaled ; venter silver scaled with a yellowish tinge 

 and with a steel-blue median longitudinal stripe, broad in front, narrow pos- 

 teriorly, becoming linear on the seventh segment; eighth segment deep blue 

 scaled beneath; lateral ciliation short, pale yellowish, eighth segment with 

 coarse black hairs. Wings narrow ; basal cross-vein oblique, reaching fourth 

 vein just behind anterior cross-vein. Legs slender, very deep violet and blue 

 scaled ; femora brassy scaled beneath ; middle tarsi with second segment brighter 

 metallic blue on outer side ; hind tarsi with fourth and fifth segments clear 

 white on outer side, black on inner side. Claw formula, 1.0-1.0-0.0. 



Length: Body 9.5 mm.; wing 7.5 mm. 



Genitalia (plate 36, fig. 241) : Side-pieces over twice as long as wide, taper- 

 ing to the narrowly rounded tips ; basal lobe low, conical, with stout setae at tip 

 and small ones basally. Clasp-filament long and slender, nearly as long as side- 

 piece, with an articulated terminal spine, and minute setae beyond middle. 

 Harpes prominent, large, concave, margin revolute, tip bent outward and 

 pointed. Unci conical at base, tips produced into long points, dentate within. 

 Basal appendages forming a rounded quadrate prominence, with setae on the two 

 lateral angles. 



Larva, Stage IV (plate 128, fig. 445). Head rounded subquadrate, slightly 

 longer than wide, front strongly emarginate at middle, with a prominent lobe 

 on each side of it. Mouth-brushes of ten lamellae, curved, inserted under 

 apices of anterior lobes. Antennae rather long, very slender, smooth, with small 

 setffi beyond middle. Dorsal head-hairs single, grouped in vicinity of antennae. 

 Eighth abdominal segment with a lateral plate with irregular angled corners, 

 bearing two stout feathered setae on its posterior border and two minute tufts. 

 Air-tube over three times as long as wide, slightly tapering outwardly, smooth, 

 a single hair-tuft close to base. Anal segment with a broad chitinoas ring 

 which bears a fringe of long spines on its posterior margin ; dorsal tufts of two 

 groups of long hairs on each side ; lateral hair thick and feathered ; ventral brush 

 well developed, composed of hairs with long featherings; anal gills short, bud- 

 shaped, rounded, subequal. 



The larvae live in the water in broken bamboo-stems. Mr. Busck and Mr. 

 Jennings obtained them only in their bamboo-traps. The prey must be the larvae 

 of the species of Hcemagogus, Wyeomyia and others that live in such locations. 

 Mr. Jennings bred one specimen, together with another of Megarliinus superbiis, 

 from a larva found in water at the leaf-bases of a terrestrial bromeliad. 



Central America. 



Bluefields, Nicaragua (W. F. Thornton) ; Tabernilla, Canal Zone, Panama, 

 May 21, 1907 (A. Busck), June 30, July 24, September 3, 1908, and February 

 4, 1909 (A. H. Jennings). Reported also by Macquart, but without locality. 



_ According to Macquart's good description, this is the species he had before 

 him under the name Megarhina ferox in 1844, but not the one so named by him 

 m 1834 (Hist. Nat. des Ins., Dipt, i, 33, 1834). This latter appears to have 

 been one of the Brazilian species not now before us. 



MEGARHINUS PORTORICENSIS von Roder. 



Megarrhina portoricensis von Roder, Ent. Zeit., Stettin, xlvi, 337, 1885 

 Megarhina portoricensis Giles, Handb. Gnats or Mosq., 133 1900 

 Megarhina sp. (from St. Domingo) Giles, Handb. Gnats or Mosq., 137, 1900. 

 Megarhmus portoricensis Theobald (in part), Mon. Culic, i, 232, 1901. 



